Distributor head for evaporators



Nov. 5, 1940; s. K. ANDERSEN DISTRIBUTOR HEAD FOR EVAPORATORS Filed Nov. 17, 1938 INVENTOR SOREN KANDERSEN ATTORNEY Patented Nov. 5, 1940 UNITED STATES DISTRIBUTOR HEAD FOR EVAPORATORS Soren K. Andersen, Racine. Wis., assignor to Young Radiator Company, Racine, Wis., a corporation of Wisconsin' Application November 17, 1938, sen-arm. 240,937

6 Claims.

The present invention relates to distributor heads for evaporators having a number of independent coils of tubes and a common outlet header wherein it is desired to supply each coil with an equal quantity of the refrigerant under all operating conditions.

Frequently the refrigerant is 25 or 50% gas when it reaches the distributor head and there is also a considerable variation in pressure and volume. Indeed the pressure, volume and per-.

cent of gas to liquid varies greatly. Therefore it clearly is difficult .to supply equal volumes of the refrigerant in whatever state it is in to the various coils.

In the present invention I provide means whereby the refrigerant is supplied in equal quantities to any number of coils regardless of its physical condition when it reaches the distributor head.

To these and other useful ends, my invention consists of parts, combinations of parts, or their equivalents and mode of operation, as hereinafter described and claimed and shown in the accompanying drawing in which:

Fig. 1 is a side 'elevation of an evaporator equipped with the preferred form of my invention.

Fig. 2 is a bottom view of the evaporator illustrated in Figure 1, a portion of the bottom plate 30 of the air duct being removed.

Fig. 3 is a top view of my improved distributor head as shown in Figure 1.

Fig. 4 is an enlarged partially sectioned side elevation of my improved distributor head taken on line 4-4 of Figure 3.

Fig. 5 is an enlarged fractional side elevation in section of one of the individual distributor tube assemblies showing a fraction of the housings and the outlet tube.

I have illustrated a four pass evaporator having a suitably designed distributor head for the same. However, my improved distributor head may be designed to serve an evaporator having any desired number of passes or sections. The evaporator shown is a conventional air cooling type having a multiplicity of closely spaced fins through which the tubes extend.

As thus illustrated, reference character A-designates the evaporator in its entirety and reference character B designates the distributor head in its entirety. The evaporator comprises four sets of coils III, II, l2 and I3, eachbeingsupported by end header plates l4 and I5, their outlets being operatively connected to an outlet 56 header it which in turn is provided with an outlet H. The inlet ends of each evaporator coil are operatively connected to the distributor head B by-means of tubes l8, I9, 20 and 2| as will hereinafter appear.

Member B is preferably positioned above or 5 near the top of the evaporator whether the inlet ends of the coils are at the top or along the side of the evaporator as in Figure 1 and comprises an elongated vertically positioned housing 24 having a lower head 25 and a suitable inlet 26 m which is preferably positioned so as to deliver the refrigerant on a tangent to the wall of the' housing for a purpose which will hereinafter appear.

I provide a top head 21 having secured therein spaced metering tubes 28, 29, 30 and 3| each being bonded to the header flanges 32 as illustrated, the bottoms terminating a short distance above member 25. as at 33. The metering tubes are each provided with narrow slits 34 which extend from or near the bottom of the tubes to a point as at 35.

I preferably provide inner housing 31 which is suitably secured to the flange of head -2'I'by means of arms 38, the bottom and top ends of the inner housing 3! terminating as at 39 and 40.

I provide inner liquid tubes 45 having a size relative to the metering tubes about as illustrated in Figure 5, the bottom terminating as at 46, the top being formed by cutting spaced slits 30 from the end downward for a short distance the free ends 41 being turned outwardly so their ends contact the walls of the metering tubes and hold their tubes concentric with the metering tubes. The lower end is expanded as'illustrated and secured to'the metering tubes. Tubes ll, I9, 20 and 2| areas illustrated, secured or bonded into the upper ends of tubes 28, 29, 30 and 3|.

As thus organized, it will be seen that the liquid refrigerant and gas entering at 26 will be separated and the liquid caused to whirl around the annular space between members 24 and 81. Some of the liquid may obviously pass over the top of member 3? and all of the liquid will accumulate in the bottom of members 24 and 31. As the liquid rise's, more and more of the slits 34 will be submerged, thus the passage of gas into the metering tubes will be more or less restricted.

I have indicated by line the liquid level within chambers 24 and 31 when the distributor is operating under certain conditions wherein there is considerable gas present. The gas clearly will pass into the metering tubes through the exposed parts of slits 84 then pass upward between the walls of the metering tubes and tubes 45 thence to the various evaporator coils.

It will be seen that the liquid level may continue to rise thus submerging more and more of the slits until resistance to the passage of gas into the metering tubes is great enough to force the liquid up into pipes 45, the increased pressure causing the liquid to rise and meet and mix with the gas at the top of pipes 28 and then pass on to the evaporator coils.

Obviously there will be times when very little gas will enter member B with the liquid; at such times the liquid will rise above line 55. In fact, it may rise to a point where it is very near the top of the slits thus the exposed part of the slits will act to meter the gas into the metering tubes and cause equal quantities of gas and liquid to enter the individual outlet tubes.

It will be seen that the liquid will rise in the housing 31 far enough to restrict the flow of gas into the metering tubes and create pressure enough to force equal volumes of liquid to the top of tubes 45 where it will be mixed with the passing gas which has been metered in equal volumes. carried into the outlet tubes and to the evaporator coils in balanced ratios.

I If, for any reason, a pass receives too little refrigerant, the pressure in this particular pass will drop, more refrigerant will then enter this pass until the distribution of refrigerant to this pass is equal to the mixture flowing through the other passes.

Clearly unit B may be designed for any desired number of passes and the unit is obviously suitable-for the on and of! system of control or for thermally controlled graduatedvalves either of which may be directly connected to inlet connection 26.

I may elect to dispense with member 31 or other minor changes may obviously be made without departing from the spirit and scope of the present invention as recited in the appended claims.

Having thus shown and described my invention, I claim:

1. A device of the class described, comprising an elongated vertically positioned chamber having a refrigerant inlet, a number of tubes positioned in said chamber the upper or outlet ends of which extend through the top of the chamber and the lower or inlet ends terminating near the bottom of the chamber, said tubes having narrow slits which extend upwardly for a distance from 5 at or near the bottoms of the tubes, inner tubes This metered mixture will, therefore, be

3. A device of the class described, comprising an elongated vertically positioned circular in cross section chamber having a refrigerant inlet, a relatively large tube positioned in said chamber the ends terminating a distance from the ends of the chamber and being positioned within said chamber to thereby form an annular space therebetween, a number of refrigerant tubes positioned within said first tube the upper or outlet ends of which extend through the top of said chamber and the lower or inlet ends terminating near the bottom of the chamber, said refrigerant tubes having narrow slits which extend upwardly for a distance from at or near the bottoms of the tubes, open end inner tubes concentrically positioned in said refrigerant tubes and extending from at or near the bottom of said refrigerant tubes to a considerable distance above the top of said slits.

4. A device as recited in claim 3 in which the inlet is arranged to divert the incoming refrigerant tangentially into the annular space.

5. A device of the class described, comprisingv the bottom to near the top of said refrigerant tubes, said inlet being positioned near the top of said chamber and having an opening positioned to thereby direct the incoming refrigerant on a tangent to the chamber adjacent the inner wall thereof.

6. A device of the class described, comprising an elongated vertically positioned chamber having a refrigerant inlet, a number of tubes longitudinally positioned'in said chamber the upper ends of which have outlets to the exterior of the chamber and the lower ends terminating near the bottom of the chamber, said tubes having narrow slits in the walls thereof which extend upwardly for a considerable distance from at or near the bottoms of the tubes, inner open end tubes concentrically positioned in said first tubes forming an annular chamber therearound and extendin from at or near the bottom to near the top of said first tubes, whereby pressure in said chambe! will cause llquid refrigerant to flow through said inner tubes into the top of said first tubes and gas will enter the portion of said slits not covered by liquid refrigerant and pass upwardly through the annular chamber formed by said first and second tubes and to the top of said first tubes, and means at the top of said inner tubes adapted to act as a transverse anchor and restrict the outlet at the top of said annular chamber. 4

BOREN K. 

